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Notwithstanding the research on refining lean tools for the sake of sustainable development is slowly progressing, sustainability-oriented application of value stream mapping has received undivided attention from practitioners and researchers. Going through the literature highlights that there is a lack of research in integrating and systematising the available knowledge on this lean tool, which is regarded as a visual process-based method to make sustainable progress over the time-based and green concepts of wastes to also assess and improve the societal sustainability performance of organisations. Hence, this paper has been aimed at presenting the findings of a systematic literature review on value stream mapping from the triple bottom line point of view. It classifies and codes the main studies in the context as well as provides a research agenda with nine recommendations that may advance this under-studied field. To narrow the gap in the current literature, this article also proposes a sustainability indicator set that would considerably contribute to guiding and strengthening the state-of-the-art research on successful implementation of the application. Besides, the findings indicate that more investigations are needed on employing survey and conceptual methodologies, applying comparative and cross-industry perspectives, developing sustainability indicator sets particularly societal metrics, and considering the stakeholders’ benefits from adopting sustainability-oriented value stream mapping. The research on the convergence of this sustainability-oriented application and new paradigms such as IR 4.0 and/or Circular Economy should be also strengthened.

Multitype quasi-cyclic (QC) low-density parity-check (LDPC) codes are a class of protograph LDPC codes lifted cyclically from protographs with multiple edges, represented by two weight and slope matrices. For a given weight-matrix, an approach is proposed to find the maximum-achievable girth $g_{\max }$ of the corresponding multitype QC-LDPC codes by some inevitable chains having less complexity than the existing methods. This advantage leads to some new patterns of the weight matrices such that the corresponding codes have some improvements in terms of the maximum-achievable girths or the minimum-distance upper-bounds. In continue, for a given weight-matrix with maximum-achievable girth $g_{\max }$ , some slope-matrices are constructed by a depth-first search algorithm for which the corresponding multitype QC-LDPC codes with even girth $g$ , $g\le g_{\max }$ , have smaller lengths, higher rates, or larger minimum-distances than the state-of-the-art achievements. Simulation results show that the constructed codes have some error-rate advantages than PEG, random-like, CCSDS, and 802.11n/ac IEEE standard LDPC codes.

This paper introduces a transactive market design for a combined heat and power (CHP) based energy hub (hub). The proposed model allows a hub operator to supply the hub’s demands by participating in the day-ahead market and a transactive market with CHPs and also in the real-time market by using a recursive moving window algorithm. The proposed local energy market for a hub operator and CHPs is based on the double auction P2P trading mechanism. The model develops an optimal bidding and offering strategies for CHPs and hub operators, respectively, to achieve optimal transactions. The CHPs may be equipped with boiler unit and heat buffer tank (HBT) beside CHP units. The uncertain nature of the hub’s electrical load, real-time and day-ahead markets prices and wind speed is addressed by using robust optimization. The procedure aimed at minimizing the worst-case CHP-based hub’s demand procurement cost even though flexibly regulating the solution robustness. Further, case studies investigate the economic impact of robustness on the hub’s cost.

This paper discusses the step and touch voltages, based on body resistance, in a grounding grid after a lightning strike at a 434-/21-kV substation. To ensure grounding grid safety, the maximum step and touch voltage should not exceed the safety criteria defined by the IEEE Std. 80. In this paper, ATP-EMTP and a genetic algorithm are used to analyze and optimize the step and touch voltages in a power grid. The voltages are calculated under normal conditions of a lightning strike at a power system. Thevenin's theorem is applied to calculate the step and touch voltages. The genetic algorithm is applied in ATP-EMTP to obtain the minimum level of step and touch voltages in the grounding grid after lightning strikes the power system. The step and touch voltages at different positions of the grounding grid are explained in this paper using the ATP-EMTP and the genetic algorithm. The computer simulation shows that the proposed scheme is highly feasible and technically attractive.

This paper analyzes the notion of resilience in power systems from a fundamental viewpoint and thoroughly examines its practical implications. This paper aims to describe and classify different high-impact rare (HR) events, provide a more technical definition of power system resilience, and discuss linkages between resilience and other well-established concepts, such as security and reliability. Most relevant decisions of system operators in the face of HR events involve a significant level of stress and strain. In order to make informed decisions within this context, it is crucial to have an all-inclusive picture of the state of the system. This paper provides an appropriate framework that not only characterizes the various states of the system but also derives informed decisions from a resilience-oriented perspective. It also describes and analyzes diverse resilience improvement strategies. Comprehensive models and classifications are provided to clearly capture various aspects of power system resilience.